Remove CXX11/ directory nesting for Tensor modules

libeigen/eigen!2199

Co-authored-by: Rasmus Munk Larsen <rmlarsen@gmail.com>

unsupported/Eigen/src/Tensor/TensorGlobalFunctions.h

@@ -0,0 +1,36 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2016 Eugene Brevdo <ebrevdo@gmail.com>
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef EIGEN_CXX11_TENSOR_TENSOR_GLOBAL_FUNCTIONS_H
+#define EIGEN_CXX11_TENSOR_TENSOR_GLOBAL_FUNCTIONS_H
+
+// IWYU pragma: private
+#include "./InternalHeaderCheck.h"
+
+namespace Eigen {
+
+/** \cpp11 \returns an expression of the coefficient-wise betainc(\a x, \a a, \a b) to the given tensors.
+ *
+ * This function computes the regularized incomplete beta function (integral).
+ *
+ */
+template <typename ADerived, typename BDerived, typename XDerived>
+EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const TensorCwiseTernaryOp<internal::scalar_betainc_op<typename XDerived::Scalar>,
+                                                                 const ADerived, const BDerived, const XDerived>
+betainc(const Eigen::TensorBase<ADerived, ReadOnlyAccessors>& a,
+        const Eigen::TensorBase<BDerived, ReadOnlyAccessors>& b,
+        const Eigen::TensorBase<XDerived, ReadOnlyAccessors>& x) {
+  return TensorCwiseTernaryOp<internal::scalar_betainc_op<typename XDerived::Scalar>, const ADerived, const BDerived,
+                              const XDerived>(a.derived(), b.derived(), x.derived(),
+                                              internal::scalar_betainc_op<typename XDerived::Scalar>());
+}
+
+}  // end namespace Eigen
+
+#endif  // EIGEN_CXX11_TENSOR_TENSOR_GLOBAL_FUNCTIONS_H